It's Official: LIGO Scientists Make First-Ever Observation of Gravity Waves (economist.com)

A few days ago, we posted reports that a major finding -- the discovery of the long-predicted gravity waves -- was expected to be formally announced today, and reader universe520 is the first to note this coverage in the Economist : It is 1.3 billion years after two black holes merged and sent out gravitational waves. On Earth in September 2015, the faintest slice of those waves was caught. That slice, called GW150914 and announced to the world on February 11th, is the first gravitational wave to be detected directly by human scientists. It is a triumph that has been a century in the making, opening a new window onto the universe and giving researchers a means to peer at hitherto inaccessible happenings, perhaps as far back in time as the Big Bang. Reader DudeTheMath adds: NPR has a nice write-up of the newly-published results: "[R]esearchers say they have detected rumblings from that cataclysmic collision as ripples in the very fabric of space-time itself. The discovery comes a century after Albert Einstein first predicted such ripples should exist. ... The signal in the detector matches well with what's predicted by Einstein's original theory, according to [Saul] Teukolsky [of Cornell], who was briefed on the results." Update: 02/11 18:08 GMT by T : Worth reading: this letter, inspirational and informative, from MIT president L. Rafael Reif, about the discovery. (Hat tip to Brian Kulak.)

Comments

Fast

[monkeyxpress]

Wow, this must be a world record for slashdot - the press release only just made it out. Having said that, this was possibly the worst kept announcement in the history of science journalism.

Why this matters

[JoshuaZ]

This matters for a bunch of reasons. First, it helps close confirm predictions of general relativity. We had a lot of evidence already but more is good. Second, if we get more data we might be able to rule out or narrow down our search space for any eventual quantum gravity theory since they have predictions about how gravity waves should behave (although this would require massively upgrading LIGO). Third, this gives us insight into stellar objects that we normally lack the ability to examine. For example, we don't know much about what the cores of neutron stars are like, but different ideas about them give different predictions about what sort of gravity waves two merging neutron stars will create. So this may give us more data about what exotic objects are actually doing. Fourth, this gives us for the first time a way of getting data from very far away sources that isn't in the electromagnetic spectrum. Right now, we can detect neutrino bursts if they come from a few million light years away but pretty much everything from outside our little galactic neighborhood has to come either from electromagnetic radiation or detecting cosmic rays. But LIGO can already detect gravity waves from events that are a billion light years away. So this gives us a whole new long type of data.

Re:Why this matters

[ganv]

I think you don't understand. We now have an entirely new way to observe what happens in regions of the universe where the mass density is high and changing. In many ways, this is like the first telescope. It is an entirely new way of observing. The reason this is so important is not the single black hole merger they detected. It is because this is the first of what will become a major source of astronomical data. Soon other frequency ranges of gravitational waves will be measurable (see LISA, https://en.wikipedia.org/wiki/...). Just because the first observation agrees with existing theory is no reason to dismiss an entirely new class of measurements as uninteresting.

buh? there's non-Human scientists?

[Thud457]

the first gravitational wave to be detected directly by human scientists

I had to go read the linked story to make sure it wasn't typical /. submitter reading failure.
Please, The Economist, do tell more, I think you buried the lead there.

sigh. At least it's not a Forbes link.

Re:So is the 5th or 6th fundamental force?

[LynnwoodRooster]

When are white holes going to be discovered? :-)

#BlackHolesMatter...

Re:Cool!

[Immerman]

Well, except for the niggling one where it demands a completely different vacuum energy level than the similarly well-tested theories of Quantum Mechanics.

It's an odd situation - we have two well-tested and widely accepted theories, neither of which show any significant cracks, but which are utterly incompatible with each other.

Re:Be Skeptical

[ledow]

Any science you can explain in a few sentences to a layman will be so full of holes as to be nothing more than hearsay and astrology.

A big event, that would have created ripples that would arrive here roughly at the time of the experiment, happened. As we listened, at that time, we saw inconsistencies representative of just such a gravitational wave hitting the experiment. It's tiny, but above background noise and experimental error (it's mentioned elsewhere that this basically means 6-sigma certainty), and coincides with a particular event that we were able to "observe" (not literally) in other ways.

The source of the wave barely matters. We detected gravitational fluxes that would otherwise be unexplained. That we are able to correlate them to one single event, that's just of the type of rare event that we predict might be able to cause such signals "loud" enough to be "heard" by us, and match up the timing means that it's the most likely explanation too.

But more importantly - 100-year-old mathematics predicts some absolutely insane, bonkers things that - when we are finally able to look for them - turn out to be true. That's all science cares about.
You can't just make up shit and then - in 100 years - several people invent an instrument that correlates perfectly to the shit you made up, several times, to the satisfaction of major scientific institutions unless - basically - you were absolutely spot-on correct all along.

That's pretty much what happened. The Einstein field equations are fucking bonkers to understand, let alone try and solve the implications of them. And I'm a mathematician. But they predict stuff like this that we then find. When it came from barely matters. A simplification of the definition of "size" in a mass-media article doesn't matter at all (tell people black holes have no size, and they look at you like you're an idiot).

So, no, it's not as bad as you make out.